Medicinal Acidic Cannabinoids

ABSTRACT

The invention relates to an acidic cannabinoid for medical use and to a  cannabis  extract comprising an acidic cannabinoid. The extract may comprise one or more compounds selected from the group consisting of cannabidiolic acid (CBD-A), cannabidiol (CBD), cannabigerolic acid (CBGA), cannabigerol (CBG), cannabinolic acid (CBN-A) and cannabinol. The invention further relates to a method for preparing a preparation comprising extracting an acidic cannabinoid from  cannabis.

RELATED APPLICATION(S)

This application is a continuation of Ser. No. 11/461,818 and filed Aug.2, 2006 which is a continuation of PCT application no.PCT/NL2005/000075, designating the United States and filed Feb. 2, 2005;which claims the benefit of the filing date of European application no.EP 04075300.6, filed Feb. 2, 2004; all of which are hereby incorporatedherein by reference in their entirety.

FIELD OF THE INVENTION

The invention relates to an acidic cannabinoid for medical use and to acannabis extract comprising an acidic cannabinoid.

BACKGROUND OF THE INVENTION

Δ⁹-Tetrahydrocannabinol (THC) is naturally found in cannabis. THC hasbeen reported to have use as an analgesic, for instance for patientssuffering from rheumatoid arthritis. A side effect of THC is itspsychoactive activity. Further, conventionally THC is administered bysmoking, which may be detrimental to general health, in particular tothe lungs and the coronary system.

WO 89/01332 describes an acidic metabolite of THC, wherein the methylgroup at the 9-position, a major metabolite formed in humans and othermammals, is substituted by a carboxyl group. This metabolite is reportedto be non-psychoactive. Its use as a therapeutic agent for such purposesas the treatment of chronic pain and tissue inflammation oftenassociated with illnesses such as rheumatoid arthritis is suggested. TheExamples show a mouse hot plate test for analgesia, which indicatesthat, in mice, the metabolite shows about the same analgesic activity asTHC and a somewhat lower activity than Naproxen. The Examples furtherindicate that the metabolite does not induce the formation of gastriclesions in an animal test under conditions wherein aspirin does.

In a review by Bhargava (Gen. Pharmac. (1978) 9(4):195-213), potentialuses of cannabinoids are mentioned in rather general terms. Bhargavamentions that several cannabinoids have been pharmacologically tested,without disclosing in any detail, a specific medical activity forcarboxylated THCs (THC acids), such as Δ⁹-tetrahydrocannabinolic acid orthe like. In addition, reference is made to the analgesic activity ofTHC and several other cannabinoids compared to morphine. THC is reportedto perform equi-analgesic with morphine, but other tested cannabinoidsare reported to be much less potent or even inactive.

Williamson and Evans (Drugs 2000, Dec. 60(6):1303-1314 discuss ingeneral terms a potential clinical use of cannabis. The specific use ofTHC acids, such as Δ⁹-tetrahydrocannabinolic acid or the like, as theactive pharmaceutical ingredient, is not disclosed.

GB-A 2 384 707 relates to the use of a cannabinoid acid, in particularcannabidiol (CBD) and cannabidiol acid (CBDA) for use as an activepharmaceutical substance in the treatment of nausea, vomiting, emisisand motion sickness. The compounds may be obtained by extraction fromcannabis. As a result of the extraction, relatively small amounts ofTHC-acids may be present in the extract, but the use of a THC-acid as anactive pharmaceutical substance is not mentioned.

SUMMARY

There remains a continuing desire for alternative therapeutics. It istherefore an object of the invention to provide such a therapeutic.

Surprisingly, it has now been found that a specific precursor of THC hasproperties which are of interest to medical use, such as analgesicand/or anti-inflammatory properties. Accordingly, the present inventionrelates to an acidic THC precursor for medical use.

More in particular, the present invention relates to an acidiccannabinoid represented by formula Ia or Ib for use as a medicament

In these formulae X, Z and A each represent a different group selectedfrom the groups —OH, hydrogen and a first alkyl; accordingly, each ofthese four groups are present in the compound. The first alkyl ispreferably a C1-C10 linear or branched alkyl, more preferably a C4-C7linear or branched alkyl, even more preferably n-pentyl. The first alkylis preferably Z.

D represents —OH or alkyl, preferably a C1-C3 linear or branched alkyl,in particular a methyl.

R represents a hydrogen, a C_(n)H_(2n)—OH, a C_(n)H_(2n)—COOH or asecond alkyl; The n in these groups is an integer, preferably 0, 1 or 2.R is preferably a C1-C3 linear or branched alkyl, more preferably —CH₃.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cannabinoid biosynthetic pathway.

FIGS. 2A and 2B show the effect of treatment with a cannabis extractcomprising THC-A on the release of TNF-α in an ELISA assay.

FIGS. 3A and 3B show respectively the inhibitory effect on TNF-α releaseand the stimulatory effect on interleukin-10 release of an unheatedcannabis extract comprising THC-A

FIG. 4 shows the effect of treatment with (an extract comprising) THC-Ain mice suffering from autoimmune encephalomyelitis.

DETAILED DESCRIPTION OF THE INVENTION

Within the context of the invention, the term “acidic” is used todescribe a compound having a carboxyl group, unless specified otherwise.In general, an acidic precursor of THC is transformable into THC bydecarboxylation, optionally in combination with one or more otherreactions, such as a cyclisation of a precursor having two of the ringsforming the core of the THC to form the third ring, (de)alkylation,(de)hydroxylation and the like. Besides the compounds of formula Ia andof Ib, examples of acidic THC precursors are cannabidiolic acid (CBDA),cannabichromenic acid (CBCA), cannabinorolic acid (CBNRA),cannabigerolic acid (CBGA), cannabinolic acid (CBNA) and functional andstructural analogues thereof. A number of these compounds are shown inthe pathway displayed in FIG. 1.

A compound according to the present invention has been found to haveanalgesic and/or anti-inflammatory activity. This is surprising, as thisfinding is contrary from what may be concluded from a standard receptorbinding test wherein the dissociation constants (K_(d)) were determinedfor binding of the compounds to the cannabinoid receptors CB1 and CB2and compared with the binding of THC (See Examples).

In particular, an acidic compound according to the invention may be usedfor relieving pain and/or for suppression of an inflammatory response,preferably for modulating the release of one or more inflammatorymediators, in particular cytokine(s), in an animal, preferably in ahuman.

In a highly preferred embodiment the acidic compound is used to suppressthe release of one or more pro-inflammatory cytokines, in particularTNF-α (tumour necrosis factor α), and/or to stimulate the release ofanti-inflammatory cytokines, in particular interleukins, more inparticular interleukin-10 (IL-10). A compound or composition that canboth suppress the release of a pro-inflammatory cytokine and stimulatethe release of an anti-inflammatory cytokine, as is provided by thepresent invention, is of considerable interest to the pharmaceuticalindustry, and medical science.

An acidic compound according to the invention may for instance be usedfor (prophylactic or therapeutic) treatment of an animal, preferably ahuman, against an inflammation, an auto-immune disease or an infection.It may also be used to alleviate symptoms, such as pain or nausea,accompanied with a disease.

In particular, a compound may be used in accordance with the inventionfor the treatment of a disease selected from the group consisting ofmultiple sclerosis, arthritis, arthrosis and other inflammatory diseasesof bone and/or joint, encephalomyelitis (in particular autoimmuneencephalomyelitis), AIDS, inflammatory bowel disease, Crohn's disease,inflammatory skin diseases (dermatitis, Psoriasis) and alleviatedsymptoms associated with cancer, anorexia, AIDS, spasticity, glaucomaand chronic pain.

Further, it has been found that a compound according to the invention isonly lowly psychoactive or even non-psychoactive. Besides, it isexpected that the risk for gastro-intestinal damage as a result of usinga compound according to the invention is low, and in particular lessthan for at least some commercially very successful drugs, e.g. aspirin.

Particularly good results have been achieved with an acidic cannabinoidaccording to Formula Ia or Ib, more in particular a compound accordingto Formula Ia, wherein Z represents the alkyl and X represents the OHand with an acidic cannabinoid according to Formula Ia or Ib, more inparticular a compound according to Formula Ia, wherein A the hydrogen.In the presence of such a compound it has been found that thesuppression of an inflammatory response, as indicated by its capacityfor suppressing TNF-α release, is high in comparison to THC, whilsthaving no noticeable detrimental psycho-active side effect. Of thesecompounds Δ⁹-tetrahydrocannabinolic acid (THC-A), is particularlypreferred. This compound is represented by Formula Ia, wherein Zrepresents n-pentyl, X is —OH, A is hydrogen, D is methyl and R ismethyl. Of this compound in particular, it has surprisingly been foundthat it is capable of both suppressing a pro-inflammatory cytokine, suchas TNF-α, and stimulating an anti-inflammatory cytokine, such asinterleukin 10.

In principle, it is possible to synthesise a compound according to theinvention (bio)chemically. The skilled person will know how to performsuch synthesis based upon common general knowledge and the presentdisclosure.

It is however an advantage of the invention that an acidiccannabinoid—in particular a compound wherein the first alkyl at thearomatic ring is n-pentyl (such as Z in formula Ia or Ib, or in theequivalent position in an acidic precursor of THC in general)—may bederived from a natural source, such as cannabis. An acidic cannabinoidcan be used (to treat a medical indication) directly without furtherchemical modifications, such as decarboxylising the compound into THCand subsequently metabolising the THC.

A compound according to the invention may be used in isolated form or inan extract from a natural source, in particular from flower tops ofcannabis. Particular suitable is a plant or a part thereof, comprisingat least 5 wt. % of acidic cannabinoids, e.g. 5-15 wt. %. Very goodresults have been achieved with Cannabis sativa, Cannabis indica.Suitable methods to extract an acidic compound according to theinvention are known in the art and include liquid extraction, e.g. withan apolar phase, such as chloroform and a polar phase, in particular analiphatic alcohol, such as methanol or ethanol. In such an extractionthe acidic cannabinoid typically is found in the apolar phase,especially if the extraction procedure is carried out at pH lower than7. The skilled person will know how to carry out a suitable extractionand further process the acidic cannabinoid, based on common generalknowledge and the information disclosed herein. It has been found thatan extract according to the invention, comprising an acidic cannabinoidis effective in reducing TNF-α excretion in human macrophages,demonstrating an inhibitory effect of the acidic cannabinoid. In anembodiment, it has further surprisingly been found to be effective inincreasing interleukin release too (see Examples).

The preparation of the extract in accordance with the invention isgenerally carried out under essentially non-decarboxylising conditionsto avoid an excessive formation of THC, which may be undesired for itspsycho-active side effects and/or for legal reasons, THC at presentbeing illicit in many states. In practice, it is therefore preferred toperform the extraction at a temperature not exceeding 95° C., morepreferably at a temperature of less then about 50° C., even morepreferably of less than about 25° C. Very good results have beenachieved with extraction at a temperature not exceeding about 4° C. Thelower limit for the temperature is not particularly critical, as long asthe extraction medium remains fluid.

The extract may then be further processed in any way, without excessiveexposure to heat to maintain essentially non-decarboxylising conditionsand thus avoid excessive formation of THC. In particular such conditionsare met if the extract is not excessively exposed to temperatures ofabout 200° C. or more. Preferably the extract is processed at atemperature not exceeding about 50° C. More preferably any furtherprocessing of the extract takes place at a temperature of about 25° C.or less. Accordingly, the solvent of the extract is preferably removedby lyophilisation.

In practice, conditions are considered to be essentiallynon-decarboxylising heat treatment is considered to be non-excessivewhen the amount of THC as a percentage of the total dry weight of theextract is less than 5 wt. %, preferably less than 2 wt. %, even morepreferably less than 0.5 wt. %. For practical reasons the amount of THCis preferably less than the maximum allowable amount to allow use as anon-prescription medicament, as determined by law. In this respect it isinteresting to note that the present invention allows for thepreparation of extracts with less than about 0.15 wt. % as a percentageof the dry weight without a need for selective removal of THC from theextract.

THC may be totally absent (i.e. non-determinable by a conventionalanalytical technique) in an extract or other composition according tothe invention. For practical reasons some THC may be present, such asabout 0.01 wt. % as a percentage of the dry weight or more.

Good results with respect to its pharmaceutical properties and low sideeffects have been achieved with an extract or other compositionaccording to the invention wherein the amount of THC as a weightpercentage of the amount of the at least one acidic cannabinoid is 0-2wt. %, preferably less than about 1 wt. %. As indicated above, THC maybe absent, although some THC may be present; as such, for practicalreasons a preferred lower limit for the amount of THC as a weightpercentage of the amount of the at least one acidic cannabinoid is about0.01 wt. %, more in particular about 0.1 wt. %.

Good results have inter alia been achieved with an extract—in particulara cannabis extract—comprising at least about 10 mg/g based upon the dryweight, preferably at least about 15 mg/g based upon the dry weight, ofthe acidic cannabinoid. Very good results have been achieved with anextract comprising at least about 20 mg/g based upon the dry weight ofthe acidic cannabinoid. The upper limit is not particularly critical.For practical reasons the upper limit is preferably about 500 mg/g, morepreferably 250 mg/g dry weight.

Preferably, a composition according to the invention, such as a(cannabis) extract, comprises at least one compound selected from thegroup consisting of cannabidiolic acid (CBD-A), cannabidiol (CBD),cannabigerolic acid (CBGA), cannabigerol (CBG), cannabinolic acid(CBN-A) and cannabinol (CBN), Cannabichromenic acid (CBC-A) andcannabichromene (CBC). In particular in such a composition alsocomprising a cannabinoid according to formula Ia or Ib, preferablyformula Ia, has been found very effective as an anti-inflammatorypreparation. The amount of the compounds of this group may be chosenwithin wide limits. Good results have inter alia been achieved with acomposition, in particular an extract, wherein the total amount of CBDand CBD-A is in the range of about 0.01-200%, more in particular about1-100 wt. % based upon the amount of the at least one acidiccannabinoid. In particular in this range indications exist that synergyoccurs.

An extract according to the invention may be employed in any form. Itmay for instance very suitably be in a dry form or in a liquid form, inparticular solubilised in ethanol, water, a vegetable oil or a liquidcomprising any of these compounds alone or in a combination.

An extract may very suitably be present in the form of a paste, cream orointment. Such form is in particular attractive for topicalapplications, e.g. for treating a dermal inflammation.

An acidic compound or extract according to the invention may verysuitably be present in a pharmaceutical preparation, further comprisinga pharmaceutically acceptable carrier. A preparation may for instancehave the form of a tincture, an ointment, a spray, an inhalant, apowder, a granulate, a suppository, a tablet or a capsule.

Of particular interest is administration as a liquid preparation fororal use or dermal application as a cream or ointment. Applications viathe nasal or inhalatory route are in particular attractive for purifiedacids.

The skilled person will know how to determine a particular dosageregime, depending upon the medical indication, the patients conditionand the type of administration.

The invention further relates to a method of treating an animal,preferably a human, with an acidic cannabinoid, which treatmentcomprises administering the acidic cannabinoid in acidic form. Thismeans in particular that the cannabinoid is administered underessentially non-decarboxylising conditions, in contrast to conventionalways of administering cannabinoids, i.e. by smoking (heating andinhaling) dried flower tops of cannabis plants. Besides avoiding thepsycho-active side-effects (as a result of the formation of THC duringheating), the present form of administration does not impose any healthrisks normally associated with smoking. Suitable forms of administrationinclude oral administration (such as ingestion or inhalation) and anyother conventional medical ways of administering a medicament.

Accordingly, the invention further relates to the use of an acidiccannabinoid, optionally in the form of an extract or a pharmaceuticalpreparation as described herein, in the manufacture of a medicament foradministration of the cannabinoid in acidic form.

The invention will now be illustrated by the following examples.

EXAMPLES Example 1 Preparation of the Extracts

Flower tops of three cannabis varieties belonging to C. sativa or C.indica and hybrids. were used to make extracts. The flower tops weredeep-frozen immediately after harvesting and thereafter lyophilised,shortly before extraction.

700 mg dried flower tops were extracted twice with 20 mLchloroform/methanol (1:9), according to the following procedure:

-   -   700 mg flower tops were mixed with 18 ml Methanol and sonicated        for 5 minutes. 2 mL chloroform were added after which the        mixture was sonicated again for 5 minutes. Extraction was then        performed (60 minutes 4° C., shaking 250 rpm). Supernatant was        removed and the extraction was repeated with the remaining        plant-pellet. Both supernatants were pooled and stored at        −20° C. until measurements started.

Composition of the Unheated Extracts

The concentration of THC-A, CBD (the total of cannabidiolic acid andcannabidiol) CBN and THC was determined with LC/MS-MS.

The results are shown in Table 1.

TABLE 1 THC-A THC CBD CBN Extract all concentrations in mg per gram dryweight. cultivar 1 202 1.43 0.21 <0.00005 cultivar 2 184 1.14 0.16<0.00005 cultivar 3 16.0 0.11 14.86 <0.00005

Example 2 Receptor Binding Studies

The affinity of the three extracts for binding to the cannabinoidreceptors CB1 and CB2 was determined in a receptor binding study. Hereina competitive assay was used between the components of the extracts andtritium labelled ligand CP55,940. The receptors were recombinant humanCB1 and CB2 co-expressed with Gαi131γ proteins in Sf9 cells

In the binding studies, unheated extracts were compared with extractsheat at 200 C to decarboxylate the THC-A. The affinity constants (K_(d))are shown in Table 2.

TABLE 2 Extract K_(d) CB1 [μM] K_(d) CB2 [μM] Cultivar 1 unheated >1 >1Cultivar 2 unheated >1 >1 Cultivar 3 unheated >1 >1 Cultivar 1 heated0.0062 0.019 Cultivar 2 heated 0.0079 0.021 Cultivar 3 heated 0.0170.023

A compound with a low K_(d) is generally considered as a potentialanti-inflammatory agent or as a potential analgesic. From the muchhigher K_(d) values from the unheated (undecarboxylated) extract, onewould expect that the acidic cannabinoids would not be promising agentsfor pain relieve or anti-inflammatory activity.

To confirm that the difference in affinity can be assigned to thecannabinoids the experiments were repeated with the purified components(obtained by fractionation on a Hypersil 10 C18 column, 250×10 mm, 10micron with 50×10 mm precolumn, Phenomenex)

The results are shown in Table 3.

TABLE 3 Extract K_(d) CB1 [μM] K_(d) CB2 [μM] THC-A >1 >1 THC 0.00380.0032 CBD 0.66 0.28 CBN* (0.036) (0.017) *the CBN was found to becontaminated with THC

Thus, based upon the binding studies it appeared that the precursors ofTHC, in particular acidic cannabinoids such as THC-A, were not apromising compound for medical use.

Example 3 Biological Immuno-System Based Assay

U937 monocytes (described e.g. in Izeboud et al., J. Rec. Sign. Tr.Research (1999), 19(1-4):191-202) were differentiated into macrophagesby treating the monocytes for 16 hours with phorbol myristate acetate(PMA)

After 48 hours storage of the macrophages in RPMI-1640 culture mediumwherein the medium was replaced every 24 hours. The macrophages wereallowed to recover from PMA treatment for 48 hours, during which culturemedium was replaced every 24 hours. At day three after PMA treatment,the macrophages were exposed to lipopolysacharide (LPS) (Sigma-Aldrich,L-2630) The macrophages were exposed to LPS in the presence or absenceof the cannabis extracts described above (in methanol). The extractswere tested undiluted and in 2.5-fold, 5-fold, 7.5-fold and 10-folddilution). In the culture medium the TNF-α level was determined a byspecific ELISA test (TNFα Cytoset, Biosource CHC1754). Further, thetoxicity of the cannabis extracts was determined with a MTT test(Sigma-Aldrich, M-2128) (also described in Mosmann, J. Immunol. Meth.1983, 55-63).

The results of the TNF-α ELISA indicated that the TNF-α release aftertreatment with unheated extract was considerably reduced, compared tothe control treatment (with an almost complete inhibition of the releasefor undiluted unheated extract). With the heated extract (wherein theTHC-A is decarboxylated), no clear effect on the TNF-α release was seen.This demonstrates that the unheated extracts are generally more potentor at least as potent in suppressing the TNFα as the heated extracts.This is an indication that an acidic precursor such as THC-A is asuitable alternative to THC as an anti-inflammatory agent andpotentially more potent than THF and/or carboxylated THF metabolites,reported previously.

The MTT tests further demonstrated that none of the tested extracts weretoxic (data not shown.)

The experiment was repeated with extracts from two cannabis cultivars,obtained by the method as described in Example 1. Part of the extractswas heated (typically 7 min. at 200° C.), the remainder was not exposedto a temperature exceeding 25° C. (typically kept refrigerated. Heatedand unheated extracts were administered in diluted form (100-fold to1000-fold dilution) to cultures of U937 cells after induction with LPS(as described above).

THC and THC-A concentrations were as shown in Table 4:

TABLE 4 THC THC-acid (mg/mL) (mg/mL) Cultivar 1 heated 4.81 0.12Cultivar 1 unheated 0.04 5.05 Cultivar 2 heated 4.37 0.09 Cultivar 2unheated 0.03 4.60

FIGS. 2A and 2B show that a considerable reduction in TNF-α was achievedwith all unheated extracts (rich in THC-A), with an (almost) completeinhibition at the 100-fold dilution. In contrast, the treatment with theheated extracts (rich in THC) did not result in a reduction of the TNF-αrelease. This demonstrates the potency of an extract according to theinvention for the treatment of an inflammation, in particular an extractobtainable by extraction under conditions at which decarboxylation isavoided, such as by extraction at a temperature below 25° C., more inparticular at a temperature of about 4° C. or less.

Example 4 Effect of Acidic Cannabinoid on Pro-Inflammatory andAnti-Inflammatory Cytokines

THC-acid was able to decrease the mRNA levels coding for TNF-alpha inisolated and cultured Peripheral Blood Mononuclear Cells (PBMC) thatwere stimulated by PHA (phytohemagglutinin) By stimulation with PHA, aresponse is induced that resembles an inflammatory reaction. TNF-alphais known as a pro-inflammatory cytokine that is released during theinitial stages of inflammation.

In the same study, the levels of mRNA coding for interleukin-10 (IL-10)were increased. IL-10 is known as an anti-inflammatory cytokine Theexperimental design of the study was as follows:

PBMC were prepared as described by Visser et al. (J. InvestigativeMedicine, 49 (2), 2001). In 6-wells plates, each well was filled with2.5 mL PBMC's (2×10⁶ cells in IMDM (Isocoves modified Dulbecco'smedium+glutamax, containing 5×10⁻⁵M 2-mercaptoethanol, 100 U/mLpenicillin, 100 U/mL streptomycin and 10% fetal calf serum)) togetherwith 500 μL THC-acid (or medium as control) and 500 μL PHA (or medium ascontrol) After incubation for 4 days (at 37° C.), total RNA was isolatedby using Trizol™ according manufactures protocol. From isolated RNA,cDNA was synthesized by using Promega Reverse Transcription Systemaccording to manufactures protocol.

The levels of cDNA were determined by means of Real Time (RT)-PCR usingTaqman® Gene Expression assay (Applied Biosystems) according tomanufactures protocol. From the levels of cDNA, the amount ofmRNA-copies as original present in the PBMC's was calculated as comparedto the housekeeping gene β-actine. The presence of THC-acid duringincubation resulted in both a decrease in the level of thepro-inflammatory cytokine TNFα and an increase in the level of theanti-inflammatory cytokine IL-10 (see FIGS. 3A and 3B). These resultsfurther support the potential of THC-acid to inhibit inflammation.

Example 5 In Vivo Study of Use of Acidic Cannabinoid in the Treatment ofEncephalomyelitis

The effect of purified THC-acid and unheated cannabis extracts weretested in vivo in a mouse model for Experimental AutoimmuneEncephalomyelitis.

In a randomized study (10 mice for each treatment) the disease wasinduced in 9 weeks old female SJL mice (Harlan) after immunization withthe proteolipid-protein as described by Nagelkerken et al.(“Interactions Do Not Play a Major Role in Inhibition of ExperimentalAutoimmune Encephalomyelitis by Anti-CD154 Monoclonal Antibodies,” J.Immunol, 173:993-999, 2004). Between day 0 and day 20 after onset of thedisease the mice were treated daily with a specified oral dose ofTHC-acid or unheated extract according to the following scheme:

Group 1: vehicle (0.2 mL olive oil/day);

Group 2: 1 mg purified THC-acid in 0.2 mL olive oil/day;

Group 3: unheated cannabis extract in 0.2 mL olive oil containing 1 mgTHC-acid/day.

The severity of the disease was followed during 42 days after onset ofthe disease by means of clinical behaviour and body weight (as describedby Nagelkerken et al. (“Interactions Do Not Play a Major Role inInhibition of Experimental Autoimmune Encephalomyelitis by Anti-CD154Monoclonal Antibodies,” J. Immunol., 173:993-999, 2004). After 42 days,the mice were sacrificed and the effect on the brainstem was studied.Treatment with 1 mg purified THC-acid or the unheated cannabis extractcontaining 1 mg THC-acid reduced the number of inflammatory cells in thebrain stem significantly as compared to vehicle.

Moreover, as shown in FIG. 4, treatment with 1 mg THC-acid or unheatedcannabis extract improved the clinical score significantly. The scoresas shown in FIG. 4 are defined as:

0: no infiltrates

-   -   1: mild perivascular accumulation    -   2: mild perivascular accumulation, multi-focal    -   3: perivascular accumulation, multiple cell layers, multi-focal.

The results in this experiment further indicate that the unheatedextract tends to be more effective than the purified THC-A (the medianscore of the experiments with the extract being 0). Based upon thisindication a multivariant analysis was performed, to verify whetherother components in the extract are likely to positively contribute tothe treatment. From the results of the multivariant analysis, it wasapparent that this indeed was the case (results not shown).

1. A method of treating a disease or symptom thereof in an animal inneed of such treatment comprising administering in acidic form as anactive ingredient an acidic cannabinoid represented by formula Ia or Ib

wherein X, Z and A each represent a different group selected from thegroups —OH, hydrogen and a first alkyl; wherein R represents a hydrogen,a C_(n)H_(2n)—OH, a C_(n)H_(2n)—COOH or a second alkyl; and wherein Drepresents hydroxyl or a third alkyl.
 2. The method according to claim1, wherein the acidic cannabinoid is Δ⁹-tetrahydrocannabinolic acid. 3.The method according to claim 1, wherein the disease is inflammatorybowel disease or Crohn's disease.
 4. The method according to claim 1,wherein the disease is multiple sclerosis, arthritis, AIDS, aninflammatory skin disease or encephalomyelitis.
 5. The method accordingto claim 4, wherein the inflammatory skin disease is dermatitis orpsoriasis.
 6. The method according to claim 1, wherein the symptom isassociated with cancer, anorexia, AIDS, spasticity, glaucoma or chronicpain.
 7. The method according to claim 1, wherein the acidic cannabinoidis used in isolated form.
 8. The method according to claim 1, whereinthe acidic cannabinoid is orally administered.
 9. The method accordingto claim 1, wherein the acidic cannabinoid is administered by dermalapplication as a cream or ointment.
 10. The method according to claim 1,wherein the acidic cannabinoid is administered in purified form via anasal or inhalatory route.
 11. The method according to claim 1, whereinthe acidic cannabinoid is administered as a preparation comprising 0-2wt. % of Δ⁹-Tetrahydrocannabinol as a weight percentage of the amount ofthe acidic cannabinoid.
 12. The method according to claim 11, whereinthe acidic cannabinoid is administered as a preparation that is free ofΔ⁹-Tetrahydrocannabinol.
 13. The method according to claim 1, whereinthe acidic cannabinoid is administered by suppository. 14.Pharmaceutical preparation comprising an acidic cannabinoid representedby formula Ia or Ib

wherein X, Z and A each represent a different group selected from thegroups —OH, hydrogen and a first alkyl; wherein R represents a hydrogen,a C_(n)H_(2n)—OH, a C_(n)H_(2n)—COOH or a second alkyl; and wherein Drepresents hydroxyl or a third alkyl; and a pharmaceutically acceptablecarrier.
 15. Pharmaceutical preparation according to claim 14, whereinthe acidic cannabinoid is Δ⁹-tetrahydrocannabinolic acid. 16.Pharmaceutical preparation according to claim 14, in the form oftinctures, ointments, sprays, inhalants, powders, granules,suppositories, creams, tablets or capsules.
 17. Pharmaceuticalpreparation according to claim 14, which preparation comprises 0-2 wt. %Δ⁹-Tetrahydrocannabinol as a weight percentage of the amount of theacidic cannabinoid.
 18. Pharmaceutical preparation according to claim14, which preparation is free of Δ⁹-Tetrahydrocannabinol.